Kubernetes Configurations

Configurations, scripts, and commands for getting k3s up and running on at least 1 server and 1 worker node.

A bit of information on my implementation can be found below, and more specific installation instructions can be found under each directory.

Directory Information

• Cluster
  • Information on how to get a k3s cluster running
• DB
  • Information for the external database for k3s master servers
• LoadBalancer
  • Information for the master server load balancer
  • This was done using nginx, but can be adapted to use any load balancer
• Rancher
  • Optional, Rancher is an open-source web-based Kubernetes orchestrator
• Workloads
  • Optional, example commands / configurations for Kubernetes workloads you can deploy

My Environment

Servers

In my environment, I'm running a total of 8 virtual machines (IP addresses for documentation reference):

• k3sServer1 (10.175.134.131)
• k3sServer2 (10.175.134.132)
• k3sAgent1 (10.175.134.141)
• k3sAgent2 (10.175.134.142)
• k3sAgent3 (10.175.134.143)
• KubeDB (10.175.134.133)
• k3sLoadBalancer (10.175.134.134)
• k3sDev (10.175.134.139)

Roles

• k3s Servers
  • Denoted as masters by Kubernetes
  • Run the kubernetes API, which drives the worker agents
  • Load Balanced
  • Configs found in Cluster/k3s-server-setup
• k3s Agents (workers)
  • Denoted as workers by Kubernetes
  • Run workloads called Pods, identical instances of the same container
  • Configs found in Cluster/k3s-agent-setup.sh
• k3s Database
  • Provides database information for the cluster
  • Each master server communicates with this
  • Agents communicate to the masters only
• Load Balancer
  • Load balances services for communication
    • For both the masters and services to be accessed
  • Configs found in LoadBalancer
• Dev Machine
  • A machine with Kubectl installed,
  • Downloaded kubeconfig from a master server
    • See Dev machine requirements

Dev Machine Requirements

To deploy workloads, you will need a separate client machine with:

• Install kubectl
  • curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add
  • sudo apt-add-repository "deb http://apt.kubernetes.io/ kubernetes-xenial main"
  • sudo apt-get install kubeadm kubelet kubectl
  • sudo apt-mark hold kubeadm kubelet kubectl
  • Verify installation with kubeadm version
• Kubeconfig from Master server
  • Connect to master server and run sudo cat /etc/rancher/k3s/k3s.yaml
  • Save these contents to ~/.kube/config